Neurological Concomitants in
By Lyn Dee Harrelson
Duffy (1995) suggests that the
etiology can be neurogenic, psychogenic, and idiopathic, while
Higgins, Chait, and Schulte (1999) argue this by stating
"Although there has been some reference to psychogenic cases
of AdSD that do respond to voice therapy, Sapir (1995) has argued
that such disorders must be clearly distinguished as nonorganic
entities that merely share some of the symptoms of AdSD."
Other similar disorders are
musculoskeletal tension dysphonia and psychogenic dysphonia.
SD is as common in women as it is in men. In the past few years there has been an increase in the number of identified cases of SD. There are some reports of a relation of SD to a familial history of the disorder.
The diagnosis of SD is very difficult. In most cases, SD is not identified usually until a year post onset. It can be triggered by a number of incidences such as a cold or flu, and is sometimes associated with a life event or trauma, while others reported that their voice disorder began with mild symptoms and developed into spasmodic dysphonia. Here are some differentiating characteristics of SD along with some similar voice disorders.
|MTD (Musculoskeletal Tension Dystonia)||
|PD (Psychogenic Dystonia)||
|SD (Spasmodic Dysphonia)||
|MTD||voice symptoms are consistent and are not
influenced by phonemic context
somewhat predictable episodes of vocal tension
tension visible during direct examination
persons respond well to voice therapy
|PD||voice problems may vary but show variability
within phonemic contexts
unique voice characteristics present with no developing patterns
possible reports of the voice returning for hours, days, weeks, or months at a time
symptoms are not present during reflexive phonation acts
respond well to voice therapy
|SD||voice has limited variability with
consistencies in various phonemic contexts
return of normal voice characteristics as with PD
symptoms reflect the nature of the underlying etiology (spastic)
do not respond well to therapy